Application research of laser interferometer to measure length of gauge blocks

The influences of gauge block gestures for calibrating coordinate measuring machine(CMM) attach importance to people more and more. In particularly, gauge block gestures for metrology CMM can not be ignored to which the accuracy of linearity measurement is hyper to 0.6μm + 1000/L. Therefore, adjustable platform is developed and single-frequency laser interferometer is adopted as measuring datum to measure the influences of length variation of gauge blocks in different gestures. At the same time, advance multi-point bracing means to reduce the length variation of gauge blocks. The results of experiments indicate that multi-point bracing means make the maximum length variation of gauge blocks to be +0.07/μm. According to the uncertainty formula of indicating error to CMM, the standard uncertainty is recalculated as u"_c = +0.73μm.